Punch press devices are in widespread use for effecting stamping, punching, and like material-forming operations. One typical form of such a punch press includes a generally inverted U-shaped frame upon which is mounted a double-acting fluid actuator or ram (either pneumatic or hydraulic), with the piston rod of the actuator extending downwardly through the press frame for reciprocable vertical movement.
This type of punch press further includes a die set which typically comprises upper and lower die plates which carry cooperating material-forming die elements. The die set may include vertically oriented guide pins for maintaining the die plates in alignment during operation of the press. In operation, the lower die plate of the die set is usually held in fixed relation with respect to the press frame, while the upper die plate is operatively connected to the piston rod of the fluid actuator for reciprocable vertical movement relative to the lower plate.
As will be appreciated, it is frequently necessary to remove the die set of the punch press from the press frame, such as for inspection, maintenance, or replacement with another die set. In the past, replacement of the die set has been undesirably time-consuming, and usually entails at least partial disassembly of the press construction. Since a mechanical clamping mechanism is frequently employed for operatively connecting the piston rod of the fluid actuator with the upper die plate, die set removal requires loosening of the clamp mechanism and detachment of the upper die plate from the piston rod, with it being necessary to reverse the sequence of steps for installation of the same or different die set. Again, these various steps must be repeated whenever removal of the die set is required, thus undesirably detracting from the overall efficiency of the material-forming operation.
In view of the above, it will be recognized that a punch press construction which facilitates convenient and efficient die set removal and installation would be very desirable for enhancing the overall efficiency of punch press operations.